1. Field of the Invention
The present disclosure relates to a light emitting device, a light source for illumination, and an illumination apparatus.
2. Description of the Related Art
Semiconductor light emitting elements such as light emitting diodes (LEDs) have a small size, a high efficiency, and a long life and thus have been considered as a future light source of various products for illumination and display, etc.
For example, for illumination, LEDs (LED chips) have been served as light sources of LED lamps. Such an LED lamp can be a bulb-shaped LED lamp (an LED bulb) as a substitute for a bulb-shaped fluorescent lamp or an incandescent lamp, or a straight tube LED lamp as a substitute for a straight tube fluorescent lamp. For example, Japanese Unexamined Patent Application Publication No. 2006-313717 discloses a conventional bulb-shaped LED lamp, and Japanese Unexamined Patent Application Publication No. 2009-043447 discloses a conventional straight tube LED lamp.
Also, the LEDs are used in an LED luminaire or the like as a substitute for a downlight, a spotlight, or the like used in a store or the like. For example, Japanese Unexamined Patent Application Publication No. 2011-210621 discloses an in-ceiling LED luminaire (downlight) that is embedded in a ceiling and emits light downward.
In the LED lamp and the LED luminaire, the LEDs are incorporated into a unit as an LED module (light emitting device) that emits light of a predetermined color such as white light. The LED lamp and the LED luminaire use, for example, a (blue-yellow-based) LED module having blue LED chips that emit blue light and yellow phosphors that are excited by the blue light to emit yellow light.